VSTO Outlook 插件：当用户拖放定期约会时，无法在 Item_Change 事件中获取 AppointmentItem答案

【问题标题】：VSTO Outlook Plugin: Cannot get AppointmentItem in Item_Change event when recurring appointment is dragged and dropped by userVSTO Outlook 插件：当用户拖放定期约会时，无法在 Item_Change 事件中获取 AppointmentItem
【发布时间】：2020-02-24 12:55:21
【问题描述】：

我想在 AppointmentItem 上捕获更改事件。我使用 Outlook 2017 进行测试。为了实现我使用：

我附上了这样的事件：

 public void AttachEvents()
        {
            _CalendarItems.ItemAdd += Item_Add;
            _CalendarItems.ItemChange += Item_Change;
            _DeletedItems.ItemAdd += Item_Delete_Add;

Item_Change 方法如下所示：

 public void Item_Change(Object item)
        {
            if (item != null && item is Outlook.AppointmentItem)
            {
                Outlook.AppointmentItem myAppointment = item as Outlook.AppointmentItem;

为了测试代码，我创建了一个定期约会系列。我双击日历中的约会并输入一些标题和正文并保存。现在我开始我的代码并检查了该项目。不幸的是，当启动项目更改时，项目指向系列而不是个人约会。启动 Item_Changed 时如何检索实际的 AppointmentItem？

相关 Stackoverflow 发帖：Outlook Addin: Moving Appointment in Calendar does not reflect new date/time in AppointmentItem (catch Calendar.ItemChange) 但仍然没有解决办法

关于这个主题的更多信息：

【问题讨论】：

标签： vsto outlook-addin

【解决方案1】：

例外不是实际的约会 - 它们作为嵌入式消息附件存储在主约会上。您获得了主约会，并且您需要访问其例外以查看发生了什么变化。

【讨论】：

【解决方案2】：

对此有一个棘手的解决方案。假设：用户使用日历视图更改项目。由于事件是由日历视图引发的，这在所有情况下都应该是正确的：

_CalendarItems = calendarFolder.Items;
_CalendarItems.ItemChange += Item_Change;

[...] 现在我们可以使用 CalendarView 计算选定的 Startdate 并将其与 RecurrencePattern 中存储的所有 Exceptions 进行比较...

if (myAppointment.IsRecurring)
                        {
                            // in case of recurring appointments at this point we always get
                            // only a reference to the series master NOT the occurrence                            
                            // Assumption: The user clicked on the AppointmentItem in the calendar view
                            // So we can calculate the selected Start Time from this selection range
                            // then compare this against all Exceptions in the OccurrencePattern of the recurring pattern
                            // if we find one AppointmentItem in the Exceptions which has the same DateTime then we found the correct one.
                            //
                            Outlook.Application application = new Outlook.Application();
                            Outlook.Explorer explorer = application.ActiveExplorer();
                            Outlook.Folder folder = explorer.CurrentFolder as Outlook.Folder;
                            Outlook.View view = explorer.CurrentView as Outlook.View;


                            // get the current calendar view
                            if (view.ViewType == Outlook.OlViewType.olCalendarView)
                            {
                                Outlook.CalendarView calView = view as Outlook.CalendarView;
                                Outlook.RecurrencePattern pattern = myAppointment.GetRecurrencePattern();

                                for (int i = 1; i <= pattern.Exceptions.Count; i++)
                                {
                                    Outlook.Exception myException = pattern.Exceptions[i];
                                    Outlook.AppointmentItem exceptionItem = myException.AppointmentItem;
                                    DateTime itemDateStart = exceptionItem.Start;
                                    if (itemDateStart == calView.SelectedStartTime)
                                    {
                                        updateMyPluginMeeting(exceptionItem);
                                        return; // the use may only select on AppointmentItem so we can skip the rest
                                    }
                                }
                            }

                        }

如果您知道任何更好的解决方案，请告诉我。

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